US20170200763A1 - Method for manufacturing image sensor structure having wide contact - Google Patents
Method for manufacturing image sensor structure having wide contact Download PDFInfo
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- US20170200763A1 US20170200763A1 US15/472,814 US201715472814A US2017200763A1 US 20170200763 A1 US20170200763 A1 US 20170200763A1 US 201715472814 A US201715472814 A US 201715472814A US 2017200763 A1 US2017200763 A1 US 2017200763A1
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Definitions
- Semiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment. Semiconductor devices are typically fabricated by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductor layers of material over a semiconductor substrate, and patterning the various material layers using lithography to form circuit components and elements thereon.
- FIG. 1 is a top-view representation of a pixel layout of an image sensor structure in accordance with some embodiments.
- FIGS. 2A to 2L are cross-sectional representations of various stages of forming the image sensor structure illustrated along line A-A′ shown in FIG. 1 in accordance with some embodiments.
- FIG. 3 is a cross-sectional representation of the image sensor structure illustrated along line B-B′ shown in FIG. 1 in accordance with some embodiments.
- FIG. 4A is a top-view representation of a pixel layout of an image sensor structure in accordance with some embodiments.
- FIG. 4B is a cross-sectional representations of the image sensor structure illustrated along line C-C′ shown in FIG. 4A in accordance with some embodiments.
- FIG. 5 is a cross-sectional representation of an image sensor structure in accordance with some embodiments.
- first and second features are formed in direct contact
- additional features may be formed between the first and second features, such that the first and second features may not be in direct contact
- present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
- spatially relative terms such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures.
- the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.
- the apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly.
- the IC structure includes an image sensor.
- the image sensor includes an isolation structure isolating two adjacent light sensing regions.
- Source/drain structures (in image sensor field, also called a floating node) are formed adjacent to the isolation structure.
- a contact is formed over the isolation structure, and the contact is wider than the isolation structure, so that the contact also covers portions of source/drain structures formed adjacent to the isolation structure. Accordingly, the source/drain structures can be electrically connected through the contact.
- FIG. 1 is a pixel layout of an image sensor structure 100 a in accordance with some embodiments.
- FIGS. 2A to 2L are cross-sectional representations of various stages of forming image sensor structure 100 a illustrated along line A-A′ shown in FIG. 1 in accordance with some embodiments. It should be noted that image sensor structure 100 a illustrated in FIGS. 2A to 2L has been simplified for the sake of clarity so that concepts of the present disclosure can be better understood. Therefore, in some other embodiments, additional features are added in image sensor structure 100 a , and some of the elements are replaced or eliminated.
- substrate 102 is received, as shown in FIG. 1A in accordance with some embodiments.
- substrate 102 is a semiconductor substrate including silicon.
- Substrate 102 may be a semiconductor wafer such as a silicon wafer.
- substrate 102 may include elementary semiconductor materials, compound semiconductor materials, and/or alloy semiconductor materials.
- the elementary semiconductor materials may be, but are not limited to, crystal silicon, polycrystalline silicon, amorphous silicon, germanium, and/or diamond.
- the compound semiconductor materials may be, but are not limited to, silicon carbide, gallium arsenic, gallium phosphide, indium phosphide, indium arsenide, and/or indium antimonide.
- the alloy semiconductor materials may be, but are not limited to, SiGe, GaAsP, AlInAs, AlGaAs, GalnAs, GaInP, and/or GaInAsP.
- substrate 102 has a front side 104 and a back side 106 .
- Isolation trenches 108 are formed in substrate 102 , as shown in FIG. 2A in accordance with some embodiments.
- isolation trenches 108 are formed by forming a hard mask structure over front side 104 of substrate 102 , patterning the hard mask structure to form openings in the hard mask structure, and etching substrate 102 through the openings. As shown in FIG. 2A , isolation trenches 108 are formed from front side 104 of substrate 102 .
- Liners 110 are formed on the bottom surface and the sidewalls of isolation trenches 108 , as shown in FIG. 2B in accordance with some embodiments.
- Liners 110 may be formed by annealing, chemical vapor deposition (CVD), physical vapor deposition, (PVD), atomic layer deposition (ALD), spin-on coating, implantation process, and/or other applicable processes.
- Liners 110 may be made of a dielectric material, such as silicon nitride, silicon oxide, silicon oxynitride, silicon carbide, or other applicable dielectric materials.
- isolation material 111 is formed in isolation trenches 108 to form isolation structures 112 , as shown in FIG. 2B in accordance with some embodiments. That is, isolation structure 112 includes liner 110 and isolation material 111 in accordance with some embodiments. However, in some other embodiments, liner 110 is not formed. In some embodiments, isolation structures 112 are deep trench isolation (DTI) structures. In some embodiments, isolation structures 112 are formed by depositing an isolation material in isolation trenches 108 . The isolation materials include silicon nitride, silicon oxide, and polysilicon in accordance with some embodiments.
- DTI deep trench isolation
- isolation structure 112 has a thickness in a range from about 1 ⁇ m to about 4 ⁇ m. The thickness of isolation structure 112 should be thick enough so that the light sensing regions formed afterwards can be separated by isolation structure 112 . In some embodiments, isolation structure 112 has a width in a range from about 0.05 ⁇ m to about 0.4 ⁇ m. If the width of isolation structure 112 is too large, the size of the light sensing regions formed afterwards may become relatively small. On the other hand, if the width of isolation structure 112 is too small, the deposition of the isolation material in isolation trench 108 may become challenging.
- isolation structure 112 is formed from front side 104 of substrate 102 , and substrate 102 is divided into a first region 114 and a second region 116 by isolation structure 112 .
- isolation structure 112 is formed, a first light sensing region 118 is formed in first region 114 of substrate 102 , and a second light sensing region 120 is formed in second region 116 of substrate 102 , as shown in FIG. 2C in accordance with some embodiments.
- first light sensing region 118 and second light sensing region 120 are no greater than (i.e. smaller than or the same as) the thickness T 1 of isolation structure 112 . That is, first light sensing region 118 and second light sensing region 120 are formed from front side 104 of substrate 102 , and the bottom surfaces of first light sensing region 118 and second light sensing region 120 are no lower than the bottom surface of isolation structure 112 , as shown in FIG. 2C in accordance with some embodiments. Since first light sensing region 118 and second light sensing region 120 are formed at the opposite sides of isolation structure 112 and has a thickness than T 1 , first light sensing region 118 and second light sensing region 120 can be isolated by isolation structure 112 .
- first light sensing region 118 and second light sensing region 120 are configured to sense (detect) light of different wavelengths.
- first light sensing region 118 and second light sensing region 120 may individually correspond to a range of wavelengths of red light, green light, or blue light.
- First light sensing region 118 and second light sensing region 120 may be doped regions having n-type and/or p-type dopants formed in substrate 102 .
- First light sensing region 118 and second light sensing region 120 may be formed by an ion implantation process, diffusion process, or other applicable processes.
- first gate structure 122 is formed over first region 114 of substrate 102
- second gate structure 124 is formed over second region 116 of substrate 102 , as shown in FIG. 2D in accordance with some embodiments.
- first gate structure 122 includes a first gate dielectric layer 126 and a first gate electrode layer 128
- second gate structure 124 includes a second gate dielectric layer 130 and a second gate electrode layer 132 .
- Spacers 134 are formed on the sidewalls of first gate structure 122 and second gate structure 124 .
- first gate dielectric layer 126 and second gate dielectric layer 130 are made of oxide. In some embodiments, first gate dielectric layer 126 and second gate dielectric layer 130 are made of high-k dielectric materials, such as metal oxides, metal nitrides, metal silicates, transition metal-oxides, transition metal-nitrides, transition metal-silicates, or oxynitrides of metals.
- high-k dielectric material examples include, but are not limited to, hafnium oxide (HfO 2 ), hafnium silicon oxide (HfSiO), hafnium silicon oxynitride (HfSiON), hafnium tantalum oxide (HfTaO), hafnium titanium oxide (HfTiO), hafnium zirconium oxide (HfZrO), zirconium oxide, titanium oxide, aluminum oxide, hafnium dioxide-alumina (HfO 2 —Al 2 O 3 ) alloy, or other applicable dielectric materials.
- first gate electrode layer 128 and second gate electrode layer 132 are made of polysilicon. In some embodiments, first gate electrode layer 128 and second gate electrode layer 132 are made of conductive materials, such as aluminum, copper, tungsten, titanium, tantalum, or other applicable materials.
- First gate structure 122 and second gate structure 124 may be formed by forming a gate dielectric layer and a conductive layer over front side 104 of substrate 102 and patterning the gate dielectric layer and the conductive layer.
- spacers 134 are made of silicon nitride, silicon oxide, silicon oxynitride, silicon oxycarbide (SiOC), silicon oxycarbon nitride (SiOCN), silicon carbide, or other applicable dielectric materials. Spacers 134 may be formed by forming a dielectric layer over front side 104 of substrate 102 to cover first gate structure 122 and second gate structure 124 and etching the dielectric layer.
- first source/drain structure 136 is formed adjacent to first gate structure 122
- a second source/drain structure 138 is formed adjacent to second gate structure 124 , as shown in FIG. 2E in accordance with some embodiments.
- first source/drain structure 136 and second source/drain structure 138 are formed by implanting dopants into substrate 102 from front side 104 of substrate 102 .
- the dopants are also doped in the upper portion of isolation structure 112 .
- first source/drain structure 136 and second source/drain structure 138 are formed by recessing front side 104 of substrate 102 to form recesses and epitaxial growing strained materials in the recesses.
- first source/drain structure 136 is formed in first region 114 of substrate 102 and is adjacent to one side of isolation structure 112
- second source/drain structure 138 is formed in second region 116 of substrate 102 and is adjacent to the other side of isolation structure 112 .
- the top surface of first source/drain structure 136 , the top surface of isolation structure 112 , and the top surface of second source/drain structure 138 are substantially level with one another.
- first source/drain structure 136 and second source/drain structure 138 are relatively small since a wide contact will be formed later on. Therefore, there can be a greater spacer to form first light sensing region 118 and second light sensing region 120 , and the quantum efficiency of the resulting image sensor 100 a can be improved (Details will be described later).
- Interlayer dielectric layer 140 is formed over front side 104 of substrate 102 , and first gate structure 122 and second gate structure 124 are covered by interlayer dielectric layer 140 , as shown in FIG. 2F in accordance with some embodiments.
- Interlayer dielectric layer 140 may include multilayers made of multiple dielectric materials, such as silicon oxide, silicon nitride, silicon oxynitride, and/or other applicable low-k dielectric materials.
- Interlayer dielectric layer 140 may be formed by chemical vapor deposition (CVD), physical vapor deposition, (PVD), atomic layer deposition (ALD), spin-on coating, or other applicable processes.
- first contact trench 142 is formed over first gate structure 122
- second contact trench 144 is formed over second gate structure 124
- wide contact trench 146 is formed over isolation structure 112 .
- wide contact trench 146 has a relatively great width. In some embodiments, the width of wide contact trench 146 is greater than the width of first contact trench 142 and the width of second contact trench 144 .
- wide contact trench 146 is greater than the width of isolation structure 122 in accordance with some embodiments. Since wide contact trench 146 is wider than isolation structure 112 , a portion of first source/drain structure 136 and a portion of second source/drain structure 138 formed adjacent to isolation structure 112 are also exposed by wide contact trench 146 , as shown in FIG. 2G in accordance with some embodiments.
- the width of wide contact trench 146 is in a range from about 0.1 ⁇ m to about 0.5 ⁇ m.
- Wide contact trench 146 should be wide enough, or the contact formed in the wide contact trench afterwards will not be wide enough to connect both first source/drain structure 136 and second source/drain structure 138 (Details will be described later).
- first contact 148 is formed in first contact trench 148 and is electrically contacted with first gate structure 122 .
- Second contact 150 is formed in second contact trench 144 and is electrically contacted with second gate structure 124 .
- Wide contact 152 is formed in wide contact trench 146 and is electrically contacted with first source/drain structure 136 and second source/drain structure 138 .
- wide contact 152 Since wide contact 152 is formed in wide contact trench 146 , wide contact 152 has a width substantially equal to the width of third contact trench, which is greater than the width of isolation structure 112 in accordance with some embodiments. Accordingly, wide contact 152 is formed on a portion of first source/drain structure 136 , isolation structure 112 , and a portion of second source/drain structure 138 in accordance with some embodiments.
- wide contact 152 overlaps with isolation structure 112 , a portion of first source/drain structure 136 , and a portion of second source/drain structure 138 .
- wide contact 152 is in direct contact with a portion of the top surface of first source/drain structure 136 , the top surface of isolation structure 112 , and a portion of the top surface of second source/drain structure 138 .
- first source/drain structure 136 and second source/drain structure 138 can be electrically connected without requiring additional conductive features.
- first source/drain structure 136 and second source/drain structure 138 are electrically connected with wide contact 152 and can be seen as a floating diffusion node.
- First contact 148 , second contact 150 , and wide contact 152 may be formed by filling first contact trench 142 , second contact trench 144 , and wide contact trench 146 by a conductive material.
- the conductive material includes aluminum (Al), copper (Cu), tungsten (W), titanium (Ti), tantulum (Ta), titanium nitride (TiN), tantalum nitride (TaN), nickel silicide (NiS), cobalt silicide (CoSi), tantulum carbide (TaC), tantulum silicide nitride (TaSiN), tantalum carbide nitride (TaCN), titanium aluminide (TiAl), titanium aluminide nitride (TiAlN), other applicable conductive materials, or a combination thereof.
- first contact 148 , second contact 150 , and wide contact 152 may further include a liner and/or a barrier layer.
- a liner (not shown) may be formed on the sidewalls and bottom of the contact trench.
- the liner may be silicon nitride, although any other applicable dielectric may alternatively be used.
- the liner may be formed using a plasma enhanced chemical vapor deposition (PECVD) process, although other applicable processes, such as physical vapor deposition or a thermal process, may alternatively be used.
- PECVD plasma enhanced chemical vapor deposition
- the barrier layer (not shown) may be formed over the liner (if present) and may cover the sidewalls and bottom of the opening.
- the barrier layer may be formed using a process such as chemical vapor deposition (CVD), physical vapor deposition (PVD), plasma enhanced CVD (PECVD), plasma enhanced physical vapor deposition (PEPVD), atomic layer deposition (ALD), or any other applicable deposition processes.
- CVD chemical vapor deposition
- PVD physical vapor deposition
- PECVD plasma enhanced CVD
- PEPVD plasma enhanced physical vapor deposition
- ALD atomic layer deposition
- the barrier layer may be made of tantalum nitride, although other materials, such as tantalum, titanium, titanium nitride, or the like, may also be used.
- interconnect structure 154 is formed over interlayer dielectric layer 140 , as shown in FIG. 2I in accordance with some embodiments. That is, interconnect structure 154 is formed over front side 104 of substrate 102 .
- interconnect structure 154 includes a dielectric layer 156 and conductive features 158 formed in dielectric layer 156 .
- dielectric layer 156 is an inter-metal dielectric (IMD) layer.
- dielectric layer 156 includes multilayers made of multiple dielectric materials, such as silicon oxide, silicon nitride, silicon oxynitride, phosphosilicate glass (PSG), borophosphosilicate glass (BPSG), or other applicable low-k dielectric materials.
- Dielectric layer 156 may be formed by a chemical vapor deposition (CVD), physical vapor deposition, (PVD), atomic layer deposition (ALD), spin-on coating, or other applicable processes.
- CVD chemical vapor deposition
- PVD physical vapor deposition
- ALD atomic layer deposition
- Conductive features 158 may be configured to connect various features or structures of image sensor structure 100 a .
- conductive features 158 are used to interconnect first contact 148 , second contact 150 , and wide contact 152 formed over substrate 102 .
- Conductive features 158 may be vertical interconnects, such as vias and contacts, and/or horizontal interconnects, such as conductive lines.
- conductive features 158 are made of conductive materials, such as aluminum, aluminum alloy, copper, copper alloy, titanium, titanium nitride, tungsten, polysilicon, or metal silicide.
- conductive features 158 shown in FIG. 2I are merely examples for better understanding the concept of the disclosure, and the scope of disclosure is not intended to be limiting. That is, conductive features 112 may be arranged in various ways in various embodiments.
- buffer layer 160 is formed over interconnect structure 154 , as shown in FIG. 2J in accordance with some embodiments.
- buffer layer 160 is made of silicon oxide, silicon nitride, or other applicable dielectric materials.
- Buffer layer 154 may be formed by CVD, PVD, or other applicable techniques.
- buffer layer 160 is planarized to form a smooth surface by a chemical-mechanical-polishing (CMP) process.
- CMP chemical-mechanical-polishing
- Carrier substrate 162 is bonded with buffer layer 160 , as shown in FIG. 2J in accordance with some embodiments.
- Carrier substrate 162 is configured to provide mechanical strength and support for processing back side 106 of substrate 102 in subsequent processes.
- Carrier substrate 162 may be similar to substrate 102 or may be a glass substrate.
- first light sensing region 118 and second light sensing region 120 are exposed from back side 106 ′ of substrate 102 ′.
- substrate 102 is polished by a chemical mechanical polishing (CMP) process.
- CMP chemical mechanical polishing
- a portion of isolation structure 120 is removed during the polishing process. Accordingly, isolation structure 112 extends from front side 104 of thinned substrate 102 ′ to thinned back side 106 ′ of thinned substrate 102 ′, as shown in FIG. 2K .
- antireflective layer 164 is formed over back side 106 ′ of thinned substrate 102 ′, such that exposed first light sensing region 118 and second light sensing region 120 are covered by antireflective layer 164 , as shown in FIG. 2L in accordance with some embodiments.
- antireflective layer 164 is made of silicon carbide nitride, silicon oxide, or the like.
- a passivation layer 166 is formed over antireflective layer 164 , as shown in FIG. 2L in accordance with some embodiments.
- passivation layer 166 is made of silicon nitride or silicon oxynitride.
- color filter layer 168 is formed over passivation layer 166 , and a microlens layer 170 is disposed over color filter layer 168 , as shown in FIG. 2L in accordance with some embodiments.
- Color filter layer 168 may include more than one color filter.
- color filter layer 168 includes a first color filter 172 and a second color filter 174 .
- first color filter 172 and second color filter 174 are respectively aligned with first light sensing region 118 and second light sensing region 120 .
- first color filter 172 and second color filter 174 are made of a dye-based (or pigment-based) polymer for filtering out a specific frequency band of radiation.
- first color filter 172 and second color filter 174 are made of resin or other organic-based material having color pigments.
- microlens layer 170 disposed on color filter layer 168 includes a first microlens 176 and a second microlens 178 . As shown in FIG. 2L , first microlens 176 and second microlens 178 are respectively aligned with first color filter 172 and second color filter 174 and therefore are respectively aligned with first light sensing region 118 and second light sensing region 120 . However, it should be noted that microlens layer 170 may be arranged in various positions in various applications.
- image sensor structure 100 a includes first region 114 and second region 116 separated by isolation structure 112 in accordance with some embodiments.
- First light sensing region 118 is formed in first region 114
- second light sensing region 120 is formed in second region 116 .
- first gate structure 122 is formed over first region 114
- first source/drain structure 136 is formed adjacent to first gate structure 122 .
- Second gate structure 124 is formed over second region 116
- second source/drain structure 138 is formed adjacent to second gate structure 124 .
- First contact 148 is formed over first gate structure 122
- second contact 150 is formed over second gate structure 124 .
- first source/drain structure 136 and second source/drain structure 138 can be directly connected by wide contact 152 . Additional conductive features and complicated manufacturing and aligning processes are not required.
- first source/drain structure 136 and second source/drain structure 138 can be relatively small.
- a shortest distance D 1 between the sidewall of first gate structure 122 and the sidewall of isolation structure 112 is smaller than 150 nm.
- a shortest distance D 1 between the sidewall of first gate structure 122 and the sidewall of isolation structure 112 is in a range from about 100 nm to about 150 nm.
- the space form forming first light sensing region 118 (or second light sensing region 120 ) can be increased. Therefore, the performance of image sensor structure 100 a can be improved.
- the width of first light sensing region 118 (or second light sensing region 120 ) is in a range from about 0.6 ⁇ m to about 0.95 ⁇ m.
- a third region 113 and a fourth region 115 are also separated by isolation structure 112 , and a third light sensing region 117 is formed in third region 113 and a fourth light sensing region 119 is formed in fourth region 115 in accordance with some embodiments.
- a third gate structure 121 is formed over third region 113 , and a third source/drain structure 135 is formed adjacent to third gate structure 121 .
- a fourth gate structure 123 is formed over fourth region 115 , and a fourth source/drain structure 137 is formed adjacent to fourth gate structure 123 .
- a third contact 147 is formed over third gate structure 121 , and a fourth contact 149 is formed over fourth gate structure 123 .
- wide contact 152 is formed over isolation structure 112 and further extends over a portion of third source/drain structure 135 and a portion of fourth source/drain structure 137 . Accordingly, first source/drain structure 136 , second source/drain structure 138 , third source/drain structure 135 , and fourth source/drain structure 137 are all directly connected by wide contact 152 in accordance with some embodiments.
- FIG. 3 is a cross-sectional representation of image sensor structure 100 a illustrated along line B-B′ shown in FIG. 1 in accordance with some embodiments.
- third light sensing region 117 and second light sensing region 120 are formed in thinned substrate 102 ′ and are separated by isolation structure 112 .
- second gate structure 124 which includes gate dielectric layer 130 and gate electrode layer 132
- third gate structure 121 which includes a gate dielectric layer 129 and a gate electrode layer 131 , are formed on front side 104 of thinned substrate 102 ′.
- antireflective layer 164 is formed over back side 106 ′ of thinned substrate 102 ′ to cover exposed third light sensing region 117 and second light sensing region 120 , and passivation layer 166 , color filter layer 168 , and microlens layer 170 are formed over antireflective layer 164 , as shown in FIG. 3 in accordance with some embodiments.
- color filter layer 168 further includes a third color filter 173
- microlens layer further includes a third microlens 177 .
- FIG. 4A is a pixel layout of an image sensor structure 100 b in accordance with some embodiments.
- FIG. 4B is a cross-sectional representation of image sensor structure 100 b illustrated along line C-C′ shown in FIG. 4A in accordance with some embodiments.
- Image sensor structure 100 b is similar to image sensor structure 100 a described previously, except hard mask structures are formed over the gate structures, so that a wide contact can be self-aligned to the source/drain structures.
- Some processes and materials used to form image sensor structure 100 b may be similar to, or the same as, those used to form image sensor structure 100 a described previously and are not repeated herein.
- a thinned substrate 102 b ′ is separated into a first region 114 b , a second region 116 b , a third region 113 b , and a fourth region 115 b by isolation structures 112 b .
- a first light sensing region 118 b , a second light sensing region 120 b , a third light sensing region 117 b , and a fourth light sensing region 119 b are formed in first region 114 b , second region 116 b , third region 113 b , and fourth region 115 b respectively.
- isolation structure 112 b includes liners 110 b and an isolation material 111 b formed between liners 110 b.
- first gate structure 122 b includes a first gate dielectric layer 126 b and a first gate electrode layer 128 b formed over first gate dielectric layer 126 b in accordance with some embodiments.
- a first hard mask structure 222 is formed over first gate structure 122 b to protect first gate structure 122 b .
- second gate structure 124 b includes a second gate dielectric layer 130 b and a second gate electrode layer 132 b formed over second gate dielectric layer 130 b in accordance with some embodiments.
- a second hard mask structure 224 is formed over second gate structure 124 b to protect second gate structure 124 b .
- Spacers 134 b are formed on the sidewalls of first gate structure 122 b and second gate structure 124 b.
- the third gate structure and the fourth gate structure may also include the similar structures as first gate structure 122 b and second gate structure 124 b do. That is, a third hard mask structure 221 and a fourth hard mask structure 223 are formed over the third gate structure and the fourth gate structure respectively, as shown in FIG. 4A in accordance with some embodiments.
- a first source/drain structure 136 b , a second source/drain structure 138 b , a third source/drain structure 135 b , and a fourth source/drain structure 137 b are formed adjacent to first gate structure 122 b , second gate structure 124 b , the third gate structure, and the fourth gate structure respectively.
- an interlayer dielectric layer 140 b is formed over a front side 104 b of thinned substrate 102 b ′ in accordance with some embodiments.
- a first contact trench is formed over first gate structure 122 b to expose the top surface of first gate structure 122 b (e.g. the top surface of first gate electrode layer 128 b ). That is, the first contact trench is formed through first hard mask structure 222 .
- a second contact trench is formed over second gate structure 124 b to expose the top surface of second gate structure 124 b (e.g. the top surface of second gate electrode layer 132 b ). That is, the second contact trench is formed through second hard mask structure 224 .
- a third contact trench and a fourth contact trench may also be formed over the third gate structure and the fourth gate structure.
- a wide contact trench is formed to expose isolation structure 112 and portions of first source/drain structure 136 b , second source/drain structure 138 b , third source/drain structure 135 b , and fourth source/drain structure 137 b .
- the wide contact trench may also be formed over portions of first gate structure 122 b , second gate structure 124 b , the third gate structure, and the fourth gate structure.
- first hard mask structure 222 , second hard mask structure 224 , third hard mask structure 221 , and fourth hard mask structure 223 are formed, so that first gate structure 122 b , second gate structure 124 b , the third gate structure, and the fourth gate structure will not be exposed by the wide contact trench.
- the wide contact trench can be self-aligned to first source/drain structure 136 b , second source/drain structure 138 b , third source/drain structure 135 b , and fourth source/drain structure 137 b , and no complicated aligning process is required.
- a first contact 148 b , a second contact 150 b , a third contact 149 b , a fourth contact 149 b , and a wide contact 152 b are formed, as shown in FIG. 4A in accordance with some embodiments. As shown in FIG. 4A in accordance with some embodiments. As shown in FIG. 4A
- wide contact 152 b is formed over first source/drain structure 136 b , second source/drain structure 138 b , third source/drain structure 135 b , and fourth source/drain structure 137 b , so that first source/drain structure 136 b , second source/drain structure 138 b , third source/drain structure 135 b , and fourth source/drain structure 137 b can be all electrically connect through wide contact 152 b . That is, additional conductive features to connect these source/drain structures are not required.
- wide contact 152 b can be formed in a self-aligned etching process. Therefore, the risk of misalignment can be prevented.
- wide contact 152 b overlaps with isolation structure 112 b , a portion of first source/drain structure 118 b , and a portion of second source/drain structure 120 b and is formed on a portion of first hard mask structure 222 .
- first source/drain structure 136 b can be self-aligned to first source/drain structure 136 b , second source/drain structure 138 b , third source/drain structure 135 b , and fourth source/drain structure 137 b , the sizes of first source/drain structure 136 b , second source/drain structure 138 b , third source/drain structure 135 b , and fourth source/drain structure 137 b can be reduced.
- a shortest distance D 2 between the sidewall of first gate structure 122 b and the sidewall of isolation structure 112 b is smaller than 100-nm.
- a shortest distance D 2 between the sidewall of first gate structure 122 b and the sidewall of isolation structure 112 b is in a range from about 50 nm to about 100 nm.
- first source/drain structure 136 b is a self-aligned contact
- second source/drain structure 138 b the size of first source/drain structure 136 b , second source/drain structure 138 b , third source/drain structure 135 b , and fourth source/drain structure 137 b can be reduced. Accordingly, the area for forming first light sensing region 118 b , second light sensing region 120 b , third light sensing region 117 b , and fourth light sensing region 119 b can be increased.
- image sensor structure 100 b also includes an interconnect structure 154 b , a buffer layer 160 b , and a carrier substrate 162 b formed over interlayer dielectric layer 140 b in accordance with some embodiments.
- Interconnect structure 154 b includes conductive features 158 b formed in a dielectric layer 156 b .
- an antireflective layer 164 b , a passivation layer 166 b , a color filter layer 168 b , and a microlens layer 170 b are formed over a thinned back side 106 b ′ of thinned substrate 102 b ′ in accordance with some embodiments.
- color filter layer 168 b includes a first color filter 172 b and a second color filter 174 b
- microlens layer 170 b includes a first microlens 176 b and a second microlens 178 b.
- FIG. 5 is a cross-sectional representation of an image sensor structure 100 c in accordance with some embodiments.
- Image sensor structure 100 c is similar to image sensor structure 100 a described previously, except the light sensing regions extend below the source/drain structures.
- Some processes and materials used to form image sensor structure 100 c may be similar to, or the same as, those used to form image sensor structure 100 a described previously and are not repeated herein.
- isolation structure 112 c includes liners 110 c and an isolation material 111 c formed between liners 110 c.
- first gate structure 122 c and a second gate structure 124 c are formed over first region 114 c and second region 116 c respectively.
- first gate structure 122 c includes a first gate dielectric layer 126 c and a first gate electrode layer 128 c formed over first gate dielectric layer 126 c in accordance with some embodiments.
- second gate structure 124 c includes a second gate dielectric layer 130 c and a second gate electrode layer 132 c formed over second gate dielectric layer 130 b in accordance with some embodiments.
- Spacers 134 c are formed on the sidewalls of first gate structure 122 c and second gate structure 124 c.
- a first source/drain structure 136 c and a second source/drain structure 138 c are formed adjacent to first gate structure 122 c and second gate structure 124 c respectively, and an interlayer dielectric layer 140 c is formed over a front side 104 c of thinned substrate 102 c ′ in accordance with some embodiments. Furthermore, a first contact 148 c , a second contact 150 c , and a wide contact 152 c are formed, as shown in FIG. 5 in accordance with some embodiments.
- image sensor structure 100 c also includes an interconnect structure 154 c , a buffer layer 160 c , and a carrier substrate 162 c formed over interlayer dielectric layer 140 c in accordance with some embodiments.
- Interconnect structure 154 c includes conductive features 158 c formed in a dielectric layer 156 c .
- an antireflective layer 164 c , a passivation layer 166 c , a color filter layer 168 c , and a microlens layer 170 c are formed over a thinned back side 106 c ′ of thinned substrate 102 c ′ in accordance with some embodiments.
- color filter layer 168 c includes a first color filter 172 c and a second color filter 174 c
- microlens layer 170 c includes a first microlens 176 c and a second microlens 178 c.
- first light sensing region 118 c includes an extending portion 218 , and extending portion 218 overlaps with a portion of first source/drain structure 136 c .
- extending portion 218 of first light sensing region 118 c has a thickness smaller than other portions of first light sensing region 118 c , so that the extending portion 218 will not be contact with first source/drain structure 136 c.
- second light sensing region 120 c includes an extending portion 220 , and extending portion 220 overlaps with a portion of second source/drain structure 138 c .
- extending portion 220 of second light sensing region 120 c has a thickness smaller than other portions of second light sensing region 120 c , so that the extending portion 220 will not be contact with second light sensing region 120 c .
- the formation of extending portions 218 and 220 enable to increase the size of the light sensing regions, and therefore the quantum efficient of image sensor structure 100 c may be improved.
- FIGS. 1 to 5 are merely examples and the scope of the disclosure is not intended to be limiting.
- the relative size of each feature in the figures may not be changed or simplified for better understanding the concept of the disclosure, but the scope of the disclosure is not intended to be limiting.
- isolation structures are used to separate neighboring light sensing regions in image sensor structures.
- isolation structure 112 (or isolation structures 112 b and 112 c ) formed by forming isolation trench 108 and depositing isolating material, such as oxide, in isolation trench 108 is formed in accordance with some embodiments. Isolation structure 112 can be seen as a deep trench isolation structure, and the risk of cross-talk and/or blooming can be reduced.
- isolation structure 112 which is formed by isolation material, is formed to separate first light sensing region 118 and second light sensing region 120 , sharing the pixels (e.g. source/drain structures) also become difficult. For example, complicated and additional conductive features may be required. However, the space for forming these conductive features may result in smaller sensing area and higher capacitance. Therefore, in some embodiments, wide contact 152 (or wide contacts 152 b and 152 c ) is formed to connect first source/drain structure 136 and second source/drain structure 138 formed at the opposite sides of isolation structure 112 . That is, additional and complicated conductive features are not required, and the size of first source/drain structure 136 and second source/drain structure 138 can be reduced. Accordingly, the capacitance of the floating diffusion node may be reduced.
- first source/drain structure 136 and second source/drain structure 138 may be reduced, the size of first light sensing region 118 and second light sensing region 120 may be enlarged. Therefore, the quantum efficiency may be increased, and the performance of image sensor structure 100 a (or image sensor structures 100 b and 100 c ) may be improved.
- first hard mask layer 222 is formed over first gate structure 122 b in accordance with some embodiments. Therefore, wide contact 152 b may be self-aligned to first light sensing region 136 b and second light sensing region 138 b . Accordingly, the size of first light sensing region 136 b and second light sensing region 138 b may be further reduced and the size of first light sensing region 118 b and second light sensing region 120 b may be further enlarged.
- the image sensor structure includes an isolation structure formed in a substrate.
- a first light sensing region is formed in a first region of the substrate, and a second light sensing region is formed in a second region of the substrate.
- a first source/drain structure is formed in the first region adjacent to one side of the isolation structure, and a second source/drain structure is formed in the second region adjacent to the other side of the isolation structure.
- a contact is formed over a portion of the first source/drain structure, the isolation structure, and a portion of the second source/drain structure, so that the first source/drain structure and the second source/drain structure can be electrically connected by the contact.
- a method for manufacturing an image sensor structure includes forming an isolation structure in a substrate to divide the substrate into a first region and a second region and forming a first light sensing region in the first region and a second light sensing region in the second region.
- the method for manufacturing the image sensor structure further includes forming a first gate structure over the first region and a second gate structure over the second region.
- the first gate structure and the second gate structure are positioned at a front side of the substrate.
- the method for manufacturing the image sensor structure further includes forming a first source/drain structure adjacent to the first gate structure and a second source/drain structure adjacent to the second gate structure and forming an interlayer dielectric layer over the front side of the substrate to cover the first gate structure and the second gate structure.
- the method for manufacturing the image sensor structure further includes forming a contact trench through the interlayer dielectric layer, such that a portion of the first source/drain structure, a portion of the second source/drain structure, and the isolation structure are exposed by the contact trench.
- the method for manufacturing the image sensor structure further includes forming a contact in the contact trench.
- a method for manufacturing an image sensor structure includes forming an isolation structure in a substrate and forming a first source/drain structure and a second source/drain structure at opposite sides of the isolation structure.
- the method for manufacturing the image sensor structure further includes forming an interlayer dielectric layer over the substrate to cover the first source/drain structure and the second source/drain structure and forming a contact trench through the interlayer dielectric layer, such that a portion of the first source/drain structure, a portion of the second source/drain structure, and the isolation structure are exposed by the contact trench.
- the method for manufacturing the image sensor structure further includes forming a contact in the contact trench.
- a method for manufacturing an image sensor structure includes forming an isolation trench in a substrate and forming an isolation structure in the isolation trench.
- the method for manufacturing the image sensor structure further includes forming a first source/drain structure and a second source/drain structure at opposite sides of the isolation structure and . . . .
- the method for manufacturing the image sensor structure further includes forming a contact over a portion of the first source/drain structure, a portion of the second source/drain structure, and the isolation structure.
Abstract
Methods for forming image sensor structures are provided. The method includes forming an isolation structure in a substrate and forming a first light sensing region and a second light sensing region. The method further includes forming a first gate structure and a second gate structure, and the first gate structure and the second gate structure are positioned at a front side of the substrate. The method further includes forming a first source/drain structure adjacent to the first gate structure and a second source/drain structure adjacent to the second gate structure and forming an interlayer dielectric layer over the front side of the substrate. The method further includes forming a contact trench through the interlayer dielectric layer and forming a contact in the contact trench.
Description
- This application is a Divisional application of U.S. patent application Ser. No. 14/928,604, filed on Oct. 30, 2015, the entirety of which is incorporated by reference herein.
- Semiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment. Semiconductor devices are typically fabricated by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductor layers of material over a semiconductor substrate, and patterning the various material layers using lithography to form circuit components and elements thereon.
- However, although existing semiconductor manufacturing processes have generally been adequate for their intended purposes, as device scaling-down continues, they have not been entirely satisfactory in all respects.
- Aspects of the present disclosure are best understood from the following detailed description when read with the accompanying figures. It should be noted that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.
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FIG. 1 is a top-view representation of a pixel layout of an image sensor structure in accordance with some embodiments. -
FIGS. 2A to 2L are cross-sectional representations of various stages of forming the image sensor structure illustrated along line A-A′ shown inFIG. 1 in accordance with some embodiments. -
FIG. 3 is a cross-sectional representation of the image sensor structure illustrated along line B-B′ shown inFIG. 1 in accordance with some embodiments. -
FIG. 4A is a top-view representation of a pixel layout of an image sensor structure in accordance with some embodiments. -
FIG. 4B is a cross-sectional representations of the image sensor structure illustrated along line C-C′ shown inFIG. 4A in accordance with some embodiments. -
FIG. 5 is a cross-sectional representation of an image sensor structure in accordance with some embodiments. - The following disclosure provides many different embodiments, or examples, for implementing different features of the invention. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
- Furthermore, spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The apparatus may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein may likewise be interpreted accordingly.
- Embodiments of an integrated circuit (IC) structure and methods for forming the same are provided. In some embodiments, the IC structure includes an image sensor. The image sensor includes an isolation structure isolating two adjacent light sensing regions. Source/drain structures (in image sensor field, also called a floating node) are formed adjacent to the isolation structure. A contact is formed over the isolation structure, and the contact is wider than the isolation structure, so that the contact also covers portions of source/drain structures formed adjacent to the isolation structure. Accordingly, the source/drain structures can be electrically connected through the contact.
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FIG. 1 is a pixel layout of animage sensor structure 100 a in accordance with some embodiments.FIGS. 2A to 2L are cross-sectional representations of various stages of formingimage sensor structure 100 a illustrated along line A-A′ shown inFIG. 1 in accordance with some embodiments. It should be noted thatimage sensor structure 100 a illustrated inFIGS. 2A to 2L has been simplified for the sake of clarity so that concepts of the present disclosure can be better understood. Therefore, in some other embodiments, additional features are added inimage sensor structure 100 a, and some of the elements are replaced or eliminated. - A
substrate 102 is received, as shown inFIG. 1A in accordance with some embodiments. In some embodiments,substrate 102 is a semiconductor substrate including silicon.Substrate 102 may be a semiconductor wafer such as a silicon wafer. Alternatively or additionally,substrate 102 may include elementary semiconductor materials, compound semiconductor materials, and/or alloy semiconductor materials. Examples of the elementary semiconductor materials may be, but are not limited to, crystal silicon, polycrystalline silicon, amorphous silicon, germanium, and/or diamond. Examples of the compound semiconductor materials may be, but are not limited to, silicon carbide, gallium arsenic, gallium phosphide, indium phosphide, indium arsenide, and/or indium antimonide. Examples of the alloy semiconductor materials may be, but are not limited to, SiGe, GaAsP, AlInAs, AlGaAs, GalnAs, GaInP, and/or GaInAsP. - As shown in
FIG. 2A ,substrate 102 has afront side 104 and aback side 106.Isolation trenches 108 are formed insubstrate 102, as shown inFIG. 2A in accordance with some embodiments. In some embodiments,isolation trenches 108 are formed by forming a hard mask structure overfront side 104 ofsubstrate 102, patterning the hard mask structure to form openings in the hard mask structure, and etchingsubstrate 102 through the openings. As shown inFIG. 2A ,isolation trenches 108 are formed fromfront side 104 ofsubstrate 102. - After
isolation trenches 108 are formed,liners 110 are formed on the bottom surface and the sidewalls ofisolation trenches 108, as shown inFIG. 2B in accordance with some embodiments.Liners 110 may be formed by annealing, chemical vapor deposition (CVD), physical vapor deposition, (PVD), atomic layer deposition (ALD), spin-on coating, implantation process, and/or other applicable processes.Liners 110 may be made of a dielectric material, such as silicon nitride, silicon oxide, silicon oxynitride, silicon carbide, or other applicable dielectric materials. - After
liners 110 are formed,isolation material 111 is formed inisolation trenches 108 to formisolation structures 112, as shown inFIG. 2B in accordance with some embodiments. That is,isolation structure 112 includesliner 110 andisolation material 111 in accordance with some embodiments. However, in some other embodiments,liner 110 is not formed. In some embodiments,isolation structures 112 are deep trench isolation (DTI) structures. In some embodiments,isolation structures 112 are formed by depositing an isolation material inisolation trenches 108. The isolation materials include silicon nitride, silicon oxide, and polysilicon in accordance with some embodiments. - In some embodiments,
isolation structure 112 has a thickness in a range from about 1 μm to about 4 μm. The thickness ofisolation structure 112 should be thick enough so that the light sensing regions formed afterwards can be separated byisolation structure 112. In some embodiments,isolation structure 112 has a width in a range from about 0.05 μm to about 0.4 μm. If the width ofisolation structure 112 is too large, the size of the light sensing regions formed afterwards may become relatively small. On the other hand, if the width ofisolation structure 112 is too small, the deposition of the isolation material inisolation trench 108 may become challenging. - As shown in
FIG. 2B ,isolation structure 112 is formed fromfront side 104 ofsubstrate 102, andsubstrate 102 is divided into afirst region 114 and asecond region 116 byisolation structure 112. Afterisolation structure 112 is formed, a firstlight sensing region 118 is formed infirst region 114 ofsubstrate 102, and a secondlight sensing region 120 is formed insecond region 116 ofsubstrate 102, as shown inFIG. 2C in accordance with some embodiments. - In some embodiments, the thickness of first
light sensing region 118 and secondlight sensing region 120 are no greater than (i.e. smaller than or the same as) the thickness T1 ofisolation structure 112. That is, firstlight sensing region 118 and secondlight sensing region 120 are formed fromfront side 104 ofsubstrate 102, and the bottom surfaces of firstlight sensing region 118 and secondlight sensing region 120 are no lower than the bottom surface ofisolation structure 112, as shown inFIG. 2C in accordance with some embodiments. Since firstlight sensing region 118 and secondlight sensing region 120 are formed at the opposite sides ofisolation structure 112 and has a thickness than T1, firstlight sensing region 118 and secondlight sensing region 120 can be isolated byisolation structure 112. - In some embodiments, first
light sensing region 118 and secondlight sensing region 120 are configured to sense (detect) light of different wavelengths. For examples, firstlight sensing region 118 and secondlight sensing region 120 may individually correspond to a range of wavelengths of red light, green light, or blue light. Firstlight sensing region 118 and secondlight sensing region 120 may be doped regions having n-type and/or p-type dopants formed insubstrate 102. Firstlight sensing region 118 and secondlight sensing region 120 may be formed by an ion implantation process, diffusion process, or other applicable processes. - After first
light sensing region 118 and secondlight sensing region 120 are formed, afirst gate structure 122 is formed overfirst region 114 ofsubstrate 102, and asecond gate structure 124 is formed oversecond region 116 ofsubstrate 102, as shown inFIG. 2D in accordance with some embodiments. In some embodiments,first gate structure 122 includes a firstgate dielectric layer 126 and a firstgate electrode layer 128, andsecond gate structure 124 includes a secondgate dielectric layer 130 and a secondgate electrode layer 132.Spacers 134 are formed on the sidewalls offirst gate structure 122 andsecond gate structure 124. - In some embodiments, first
gate dielectric layer 126 and secondgate dielectric layer 130 are made of oxide. In some embodiments, firstgate dielectric layer 126 and secondgate dielectric layer 130 are made of high-k dielectric materials, such as metal oxides, metal nitrides, metal silicates, transition metal-oxides, transition metal-nitrides, transition metal-silicates, or oxynitrides of metals. Examples of the high-k dielectric material include, but are not limited to, hafnium oxide (HfO2), hafnium silicon oxide (HfSiO), hafnium silicon oxynitride (HfSiON), hafnium tantalum oxide (HfTaO), hafnium titanium oxide (HfTiO), hafnium zirconium oxide (HfZrO), zirconium oxide, titanium oxide, aluminum oxide, hafnium dioxide-alumina (HfO2—Al2O3) alloy, or other applicable dielectric materials. - In some embodiments, first
gate electrode layer 128 and secondgate electrode layer 132 are made of polysilicon. In some embodiments, firstgate electrode layer 128 and secondgate electrode layer 132 are made of conductive materials, such as aluminum, copper, tungsten, titanium, tantalum, or other applicable materials.First gate structure 122 andsecond gate structure 124 may be formed by forming a gate dielectric layer and a conductive layer overfront side 104 ofsubstrate 102 and patterning the gate dielectric layer and the conductive layer. - In some embodiments,
spacers 134 are made of silicon nitride, silicon oxide, silicon oxynitride, silicon oxycarbide (SiOC), silicon oxycarbon nitride (SiOCN), silicon carbide, or other applicable dielectric materials.Spacers 134 may be formed by forming a dielectric layer overfront side 104 ofsubstrate 102 to coverfirst gate structure 122 andsecond gate structure 124 and etching the dielectric layer. - After
first gate structure 122 andsecond gate structure 124 are formed, a first source/drain structure 136 is formed adjacent tofirst gate structure 122, and a second source/drain structure 138 is formed adjacent tosecond gate structure 124, as shown inFIG. 2E in accordance with some embodiments. In some embodiments, first source/drain structure 136 and second source/drain structure 138 are formed by implanting dopants intosubstrate 102 fromfront side 104 ofsubstrate 102. In some embodiments, the dopants are also doped in the upper portion ofisolation structure 112. In some embodiments, first source/drain structure 136 and second source/drain structure 138 are formed by recessingfront side 104 ofsubstrate 102 to form recesses and epitaxial growing strained materials in the recesses. - As shown in
FIG. 2E , first source/drain structure 136 is formed infirst region 114 ofsubstrate 102 and is adjacent to one side ofisolation structure 112, and second source/drain structure 138 is formed insecond region 116 ofsubstrate 102 and is adjacent to the other side ofisolation structure 112. In some embodiments, the top surface of first source/drain structure 136, the top surface ofisolation structure 112, and the top surface of second source/drain structure 138 are substantially level with one another. - In some embodiments, the sizes of first source/
drain structure 136 and second source/drain structure 138 are relatively small since a wide contact will be formed later on. Therefore, there can be a greater spacer to form firstlight sensing region 118 and secondlight sensing region 120, and the quantum efficiency of the resultingimage sensor 100 a can be improved (Details will be described later). - After first source/
drain structure 136 and second source/drain structure 138 are formed, aninterlayer dielectric layer 140 is formed overfront side 104 ofsubstrate 102, andfirst gate structure 122 andsecond gate structure 124 are covered byinterlayer dielectric layer 140, as shown inFIG. 2F in accordance with some embodiments.Interlayer dielectric layer 140 may include multilayers made of multiple dielectric materials, such as silicon oxide, silicon nitride, silicon oxynitride, and/or other applicable low-k dielectric materials.Interlayer dielectric layer 140 may be formed by chemical vapor deposition (CVD), physical vapor deposition, (PVD), atomic layer deposition (ALD), spin-on coating, or other applicable processes. - Next, a
first contact trench 142, asecond contact trench 144, and awide contact trench 146 are formed throughinterlayer dielectric layer 140, as shown inFIG. 2G in accordance with some embodiments.First contact trench 142 is formed overfirst gate structure 122,second contact trench 144 is formed oversecond gate structure 124, andwide contact trench 146 is formed overisolation structure 112. In addition, as shown inFIG. 2G ,wide contact trench 146 has a relatively great width. In some embodiments, the width ofwide contact trench 146 is greater than the width offirst contact trench 142 and the width ofsecond contact trench 144. - Furthermore, the width of
wide contact trench 146 is greater than the width ofisolation structure 122 in accordance with some embodiments. Sincewide contact trench 146 is wider thanisolation structure 112, a portion of first source/drain structure 136 and a portion of second source/drain structure 138 formed adjacent toisolation structure 112 are also exposed bywide contact trench 146, as shown inFIG. 2G in accordance with some embodiments. - In some embodiments, the width of
wide contact trench 146 is in a range from about 0.1 μm to about 0.5 μm.Wide contact trench 146 should be wide enough, or the contact formed in the wide contact trench afterwards will not be wide enough to connect both first source/drain structure 136 and second source/drain structure 138 (Details will be described later). - After
first contact trench 142,second contact trench 144, andwide contact trench 146 are formed, afirst contact 148, asecond contact 150, and awide contact 152 are formed, as shown inFIG. 2H in accordance with some embodiments.First contact 148 is formed infirst contact trench 148 and is electrically contacted withfirst gate structure 122.Second contact 150 is formed insecond contact trench 144 and is electrically contacted withsecond gate structure 124.Wide contact 152 is formed inwide contact trench 146 and is electrically contacted with first source/drain structure 136 and second source/drain structure 138. - Since
wide contact 152 is formed inwide contact trench 146,wide contact 152 has a width substantially equal to the width of third contact trench, which is greater than the width ofisolation structure 112 in accordance with some embodiments. Accordingly,wide contact 152 is formed on a portion of first source/drain structure 136,isolation structure 112, and a portion of second source/drain structure 138 in accordance with some embodiments. - As shown in
FIG. 2H ,wide contact 152 overlaps withisolation structure 112, a portion of first source/drain structure 136, and a portion of second source/drain structure 138. In some embodiments,wide contact 152 is in direct contact with a portion of the top surface of first source/drain structure 136, the top surface ofisolation structure 112, and a portion of the top surface of second source/drain structure 138. By formingwide contact 152 having a relatively great width, first source/drain structure 136 and second source/drain structure 138 can be electrically connected without requiring additional conductive features. In some embodiments, first source/drain structure 136 and second source/drain structure 138 are electrically connected withwide contact 152 and can be seen as a floating diffusion node. -
First contact 148,second contact 150, andwide contact 152 may be formed by fillingfirst contact trench 142,second contact trench 144, andwide contact trench 146 by a conductive material. In some embodiments, the conductive material includes aluminum (Al), copper (Cu), tungsten (W), titanium (Ti), tantulum (Ta), titanium nitride (TiN), tantalum nitride (TaN), nickel silicide (NiS), cobalt silicide (CoSi), tantulum carbide (TaC), tantulum silicide nitride (TaSiN), tantalum carbide nitride (TaCN), titanium aluminide (TiAl), titanium aluminide nitride (TiAlN), other applicable conductive materials, or a combination thereof. - In addition,
first contact 148,second contact 150, andwide contact 152 may further include a liner and/or a barrier layer. For example, a liner (not shown) may be formed on the sidewalls and bottom of the contact trench. The liner may be silicon nitride, although any other applicable dielectric may alternatively be used. The liner may be formed using a plasma enhanced chemical vapor deposition (PECVD) process, although other applicable processes, such as physical vapor deposition or a thermal process, may alternatively be used. The barrier layer (not shown) may be formed over the liner (if present) and may cover the sidewalls and bottom of the opening. The barrier layer may be formed using a process such as chemical vapor deposition (CVD), physical vapor deposition (PVD), plasma enhanced CVD (PECVD), plasma enhanced physical vapor deposition (PEPVD), atomic layer deposition (ALD), or any other applicable deposition processes. The barrier layer may be made of tantalum nitride, although other materials, such as tantalum, titanium, titanium nitride, or the like, may also be used. - After
first contact 148,second contact 150, andwide contact 152 are formed, aninterconnect structure 154 is formed overinterlayer dielectric layer 140, as shown inFIG. 2I in accordance with some embodiments. That is,interconnect structure 154 is formed overfront side 104 ofsubstrate 102. In some embodiments,interconnect structure 154 includes adielectric layer 156 andconductive features 158 formed indielectric layer 156. - In some embodiments,
dielectric layer 156 is an inter-metal dielectric (IMD) layer. In some embodiments,dielectric layer 156 includes multilayers made of multiple dielectric materials, such as silicon oxide, silicon nitride, silicon oxynitride, phosphosilicate glass (PSG), borophosphosilicate glass (BPSG), or other applicable low-k dielectric materials.Dielectric layer 156 may be formed by a chemical vapor deposition (CVD), physical vapor deposition, (PVD), atomic layer deposition (ALD), spin-on coating, or other applicable processes. - Conductive features 158 may be configured to connect various features or structures of
image sensor structure 100 a. For example,conductive features 158 are used to interconnectfirst contact 148,second contact 150, andwide contact 152 formed oversubstrate 102. Conductive features 158 may be vertical interconnects, such as vias and contacts, and/or horizontal interconnects, such as conductive lines. In some embodiments,conductive features 158 are made of conductive materials, such as aluminum, aluminum alloy, copper, copper alloy, titanium, titanium nitride, tungsten, polysilicon, or metal silicide. - It should be noted that
conductive features 158 shown inFIG. 2I are merely examples for better understanding the concept of the disclosure, and the scope of disclosure is not intended to be limiting. That is,conductive features 112 may be arranged in various ways in various embodiments. - After
interconnect structure 154 is formed, abuffer layer 160 is formed overinterconnect structure 154, as shown inFIG. 2J in accordance with some embodiments. In some embodiments,buffer layer 160 is made of silicon oxide, silicon nitride, or other applicable dielectric materials.Buffer layer 154 may be formed by CVD, PVD, or other applicable techniques. In some embodiments,buffer layer 160 is planarized to form a smooth surface by a chemical-mechanical-polishing (CMP) process. - Next, a
carrier substrate 162 is bonded withbuffer layer 160, as shown inFIG. 2J in accordance with some embodiments.Carrier substrate 162 is configured to provide mechanical strength and support for processing backside 106 ofsubstrate 102 in subsequent processes.Carrier substrate 162 may be similar tosubstrate 102 or may be a glass substrate. - Afterwards, back
side 106 ofsubstrate 106 is polished to expose firstlight sensing region 118 and secondlight sensing region 120, as shown inFIG. 2K in accordance with some embodiments. Accordingly, a thinnedsubstrate 102′ having aback side 106′ is formed. As shown inFIG. 2K , firstlight sensing region 118 and secondlight sensing region 120 are exposed fromback side 106′ ofsubstrate 102′. In some embodiments,substrate 102 is polished by a chemical mechanical polishing (CMP) process. In some embodiments, a portion ofisolation structure 120 is removed during the polishing process. Accordingly,isolation structure 112 extends fromfront side 104 of thinnedsubstrate 102′ to thinned backside 106′ of thinnedsubstrate 102′, as shown inFIG. 2K . - Next,
antireflective layer 164 is formed overback side 106′ of thinnedsubstrate 102′, such that exposed firstlight sensing region 118 and secondlight sensing region 120 are covered byantireflective layer 164, as shown inFIG. 2L in accordance with some embodiments. In some embodiments,antireflective layer 164 is made of silicon carbide nitride, silicon oxide, or the like. Afterantireflective layer 164 is formed, apassivation layer 166 is formed overantireflective layer 164, as shown inFIG. 2L in accordance with some embodiments. In some embodiments,passivation layer 166 is made of silicon nitride or silicon oxynitride. - After
passivation layer 166 is formed,color filter layer 168 is formed overpassivation layer 166, and amicrolens layer 170 is disposed overcolor filter layer 168, as shown inFIG. 2L in accordance with some embodiments.Color filter layer 168 may include more than one color filter. In some embodiments,color filter layer 168 includes afirst color filter 172 and asecond color filter 174. In some embodiments,first color filter 172 andsecond color filter 174 are respectively aligned with firstlight sensing region 118 and secondlight sensing region 120. In some embodiments,first color filter 172 andsecond color filter 174 are made of a dye-based (or pigment-based) polymer for filtering out a specific frequency band of radiation. In some embodiments,first color filter 172 andsecond color filter 174 are made of resin or other organic-based material having color pigments. - In some embodiments,
microlens layer 170 disposed oncolor filter layer 168 includes afirst microlens 176 and asecond microlens 178. As shown inFIG. 2L ,first microlens 176 andsecond microlens 178 are respectively aligned withfirst color filter 172 andsecond color filter 174 and therefore are respectively aligned with firstlight sensing region 118 and secondlight sensing region 120. However, it should be noted thatmicrolens layer 170 may be arranged in various positions in various applications. - Referring back to
FIG. 1 ,image sensor structure 100 a includesfirst region 114 andsecond region 116 separated byisolation structure 112 in accordance with some embodiments. Firstlight sensing region 118 is formed infirst region 114, and secondlight sensing region 120 is formed insecond region 116. In addition,first gate structure 122 is formed overfirst region 114, and first source/drain structure 136 is formed adjacent tofirst gate structure 122.Second gate structure 124 is formed oversecond region 116, and second source/drain structure 138 is formed adjacent tosecond gate structure 124.First contact 148 is formed overfirst gate structure 122, andsecond contact 150 is formed oversecond gate structure 124. - As described previously, the relatively
wide contact 152 is formed overisolation structure 112 and further extends over a portion of first source/drain structure 136 and a portion of second source/drain structure 138. Accordingly, first source/drain structure 136 and second source/drain structure 138 can be directly connected bywide contact 152. Additional conductive features and complicated manufacturing and aligning processes are not required. - In addition, the formation of
wide contact 152 enables to save the space for forming additional conductive features. Therefore, the size of first source/drain structure 136 and second source/drain structure 138 can be relatively small. In some embodiments, a shortest distance D1 between the sidewall offirst gate structure 122 and the sidewall ofisolation structure 112 is smaller than 150 nm. In some embodiments, a shortest distance D1 between the sidewall offirst gate structure 122 and the sidewall ofisolation structure 112 is in a range from about 100 nm to about 150 nm. When the distance between first gate structure 122 (or second gate structure 124) andisolation structure 112 is reduced, the space form forming first light sensing region 118 (or second light sensing region 120) can be increased. Therefore, the performance ofimage sensor structure 100 a can be improved. In some embodiments, the width of first light sensing region 118 (or second light sensing region 120) is in a range from about 0.6 μm to about 0.95 μm. - Similarly, a
third region 113 and afourth region 115 are also separated byisolation structure 112, and a thirdlight sensing region 117 is formed inthird region 113 and a fourthlight sensing region 119 is formed infourth region 115 in accordance with some embodiments. In addition, athird gate structure 121 is formed overthird region 113, and a third source/drain structure 135 is formed adjacent tothird gate structure 121. Afourth gate structure 123 is formed overfourth region 115, and a fourth source/drain structure 137 is formed adjacent tofourth gate structure 123. In addition, athird contact 147 is formed overthird gate structure 121, and afourth contact 149 is formed overfourth gate structure 123. Similar to those described previously,wide contact 152 is formed overisolation structure 112 and further extends over a portion of third source/drain structure 135 and a portion of fourth source/drain structure 137. Accordingly, first source/drain structure 136, second source/drain structure 138, third source/drain structure 135, and fourth source/drain structure 137 are all directly connected bywide contact 152 in accordance with some embodiments. -
FIG. 3 is a cross-sectional representation ofimage sensor structure 100 a illustrated along line B-B′ shown inFIG. 1 in accordance with some embodiments. As shown inFIG. 3 , thirdlight sensing region 117 and secondlight sensing region 120 are formed in thinnedsubstrate 102′ and are separated byisolation structure 112. In addition,second gate structure 124, which includesgate dielectric layer 130 andgate electrode layer 132, andthird gate structure 121, which includes agate dielectric layer 129 and agate electrode layer 131, are formed onfront side 104 of thinnedsubstrate 102′. - As described previously,
antireflective layer 164 is formed overback side 106′ of thinnedsubstrate 102′ to cover exposed thirdlight sensing region 117 and secondlight sensing region 120, andpassivation layer 166,color filter layer 168, andmicrolens layer 170 are formed overantireflective layer 164, as shown inFIG. 3 in accordance with some embodiments. In addition,color filter layer 168 further includes athird color filter 173, and microlens layer further includes athird microlens 177. - As shown in
FIG. 3 , althoughwide contact 152 formed overisolation structure 112 has a relatively great width, the contacts formed at other portions ofimage sensor structure 100 a may still remain their original widths. Therefore, the process described above may be applied to present manufacturing processes without using complicated additional processes or altering too many original processes. -
FIG. 4A is a pixel layout of animage sensor structure 100 b in accordance with some embodiments.FIG. 4B is a cross-sectional representation ofimage sensor structure 100 b illustrated along line C-C′ shown inFIG. 4A in accordance with some embodiments.Image sensor structure 100 b is similar toimage sensor structure 100 a described previously, except hard mask structures are formed over the gate structures, so that a wide contact can be self-aligned to the source/drain structures. Some processes and materials used to formimage sensor structure 100 b may be similar to, or the same as, those used to formimage sensor structure 100 a described previously and are not repeated herein. - Similar to image
sensor structure 100 a, a thinnedsubstrate 102 b′ is separated into afirst region 114 b, asecond region 116 b, a third region 113 b, and afourth region 115 b byisolation structures 112 b. A firstlight sensing region 118 b, a secondlight sensing region 120 b, a third light sensing region 117 b, and a fourthlight sensing region 119 b are formed infirst region 114 b,second region 116 b, third region 113 b, andfourth region 115 b respectively. In some embodiments,isolation structure 112 b includesliners 110 b and anisolation material 111 b formed betweenliners 110 b. - In addition, a
first gate structure 122 b, asecond gate structure 124 b, a third gate structure (not shown), and a fourth gate structure (not shown) are formed overfirst region 114 b,second region 116 b, third region 113 b, andfourth region 115 b respectively. As shown inFIG. 4B ,first gate structure 122 b includes a firstgate dielectric layer 126 b and a firstgate electrode layer 128 b formed over firstgate dielectric layer 126 b in accordance with some embodiments. In addition, a firsthard mask structure 222 is formed overfirst gate structure 122 b to protectfirst gate structure 122 b. Similarly,second gate structure 124 b includes a secondgate dielectric layer 130 b and a secondgate electrode layer 132 b formed over secondgate dielectric layer 130 b in accordance with some embodiments. In addition, a secondhard mask structure 224 is formed oversecond gate structure 124 b to protectsecond gate structure 124 b.Spacers 134 b are formed on the sidewalls offirst gate structure 122 b andsecond gate structure 124 b. - It should be noted that, although not shown in the figures, the third gate structure and the fourth gate structure may also include the similar structures as
first gate structure 122 b andsecond gate structure 124 b do. That is, a thirdhard mask structure 221 and a fourthhard mask structure 223 are formed over the third gate structure and the fourth gate structure respectively, as shown inFIG. 4A in accordance with some embodiments. - Next, a first source/
drain structure 136 b, a second source/drain structure 138 b, a third source/drain structure 135 b, and a fourth source/drain structure 137 b are formed adjacent tofirst gate structure 122 b,second gate structure 124 b, the third gate structure, and the fourth gate structure respectively. Afterwards, aninterlayer dielectric layer 140 b is formed over afront side 104 b of thinnedsubstrate 102 b′ in accordance with some embodiments. - A first contact trench is formed over
first gate structure 122 b to expose the top surface offirst gate structure 122 b (e.g. the top surface of firstgate electrode layer 128 b). That is, the first contact trench is formed through firsthard mask structure 222. In addition, a second contact trench is formed oversecond gate structure 124 b to expose the top surface ofsecond gate structure 124 b (e.g. the top surface of secondgate electrode layer 132 b). That is, the second contact trench is formed through secondhard mask structure 224. A third contact trench and a fourth contact trench may also be formed over the third gate structure and the fourth gate structure. - Furthermore, a wide contact trench is formed to expose
isolation structure 112 and portions of first source/drain structure 136 b, second source/drain structure 138 b, third source/drain structure 135 b, and fourth source/drain structure 137 b. In addition, the wide contact trench may also be formed over portions offirst gate structure 122 b,second gate structure 124 b, the third gate structure, and the fourth gate structure. However, as described above, firsthard mask structure 222, secondhard mask structure 224, thirdhard mask structure 221, and fourthhard mask structure 223 are formed, so thatfirst gate structure 122 b,second gate structure 124 b, the third gate structure, and the fourth gate structure will not be exposed by the wide contact trench. Accordingly, the wide contact trench can be self-aligned to first source/drain structure 136 b, second source/drain structure 138 b, third source/drain structure 135 b, and fourth source/drain structure 137 b, and no complicated aligning process is required. - Next, a
first contact 148 b, asecond contact 150 b, athird contact 149 b, afourth contact 149 b, and awide contact 152 b are formed, as shown inFIG. 4A in accordance with some embodiments. As shown inFIG. 4A ,wide contact 152 b is formed over first source/drain structure 136 b, second source/drain structure 138 b, third source/drain structure 135 b, and fourth source/drain structure 137 b, so that first source/drain structure 136 b, second source/drain structure 138 b, third source/drain structure 135 b, and fourth source/drain structure 137 b can be all electrically connect throughwide contact 152 b. That is, additional conductive features to connect these source/drain structures are not required. - In addition, since first
hard mask structure 222, secondhard mask structure 224, thirdhard mask structure 221, and fourthhard mask structure 223 are formed,wide contact 152 b can be formed in a self-aligned etching process. Therefore, the risk of misalignment can be prevented. In some embodiments,wide contact 152 b overlaps withisolation structure 112 b, a portion of first source/drain structure 118 b, and a portion of second source/drain structure 120 b and is formed on a portion of firsthard mask structure 222. - In addition, since
wide contact 152 b can be self-aligned to first source/drain structure 136 b, second source/drain structure 138 b, third source/drain structure 135 b, and fourth source/drain structure 137 b, the sizes of first source/drain structure 136 b, second source/drain structure 138 b, third source/drain structure 135 b, and fourth source/drain structure 137 b can be reduced. In some embodiments, a shortest distance D2 between the sidewall offirst gate structure 122 b and the sidewall ofisolation structure 112 b is smaller than 100-nm. In some embodiments, a shortest distance D2 between the sidewall offirst gate structure 122 b and the sidewall ofisolation structure 112 b is in a range from about 50 nm to about 100 nm. When the distance betweenfirst gate structure 122 b andisolation structure 112 b is reduced, the space form forming firstlight sensing region 118 b can be increased. Therefore, the performance ofimage sensor structure 100 b can be improved. - Furthermore, as shown in
FIG. 4A , sincewide contact 152 b is a self-aligned contact, the size of first source/drain structure 136 b, second source/drain structure 138 b, third source/drain structure 135 b, and fourth source/drain structure 137 b can be reduced. Accordingly, the area for forming firstlight sensing region 118 b, secondlight sensing region 120 b, third light sensing region 117 b, and fourthlight sensing region 119 b can be increased. - Similar to image
sensor structure 100 a,image sensor structure 100 b also includes aninterconnect structure 154 b, abuffer layer 160 b, and acarrier substrate 162 b formed overinterlayer dielectric layer 140 b in accordance with some embodiments.Interconnect structure 154 b includesconductive features 158 b formed in adielectric layer 156 b. In addition, anantireflective layer 164 b, apassivation layer 166 b, acolor filter layer 168 b, and amicrolens layer 170 b are formed over a thinned backside 106 b′ of thinnedsubstrate 102 b′ in accordance with some embodiments. In some embodiments,color filter layer 168 b includes afirst color filter 172 b and asecond color filter 174 b, andmicrolens layer 170 b includes afirst microlens 176 b and asecond microlens 178 b. -
FIG. 5 is a cross-sectional representation of animage sensor structure 100 c in accordance with some embodiments.Image sensor structure 100 c is similar toimage sensor structure 100 a described previously, except the light sensing regions extend below the source/drain structures. Some processes and materials used to formimage sensor structure 100 c may be similar to, or the same as, those used to formimage sensor structure 100 a described previously and are not repeated herein. - Similar to image
sensor structure 100 a, a thinnedsubstrate 102 c′ is separated into afirst region 114 c and asecond region 116 c, and a firstlight sensing region 118 c and a secondlight sensing region 120 c are formed infirst region 114 c andsecond region 116 c respectively. In some embodiments,isolation structure 112 c includesliners 110 c and anisolation material 111 c formed betweenliners 110 c. - In addition, a
first gate structure 122 c and asecond gate structure 124 c are formed overfirst region 114 c andsecond region 116 c respectively. As shown inFIG. 5 ,first gate structure 122 c includes a firstgate dielectric layer 126 c and a firstgate electrode layer 128 c formed over firstgate dielectric layer 126 c in accordance with some embodiments. Similarly,second gate structure 124 c includes a secondgate dielectric layer 130 c and a secondgate electrode layer 132 c formed over secondgate dielectric layer 130 b in accordance with some embodiments.Spacers 134 c are formed on the sidewalls offirst gate structure 122 c andsecond gate structure 124 c. - A first source/
drain structure 136 c and a second source/drain structure 138 c are formed adjacent tofirst gate structure 122 c andsecond gate structure 124 c respectively, and aninterlayer dielectric layer 140 c is formed over afront side 104 c of thinnedsubstrate 102 c′ in accordance with some embodiments. Furthermore, afirst contact 148 c, asecond contact 150 c, and awide contact 152 c are formed, as shown inFIG. 5 in accordance with some embodiments. - Similar to image
sensor structure 100 a,image sensor structure 100 c also includes aninterconnect structure 154 c, abuffer layer 160 c, and acarrier substrate 162 c formed overinterlayer dielectric layer 140 c in accordance with some embodiments.Interconnect structure 154 c includesconductive features 158 c formed in adielectric layer 156 c. In addition, anantireflective layer 164 c, a passivation layer 166 c, acolor filter layer 168 c, and amicrolens layer 170 c are formed over a thinned backside 106 c′ of thinnedsubstrate 102 c′ in accordance with some embodiments. In some embodiments,color filter layer 168 c includes afirst color filter 172 c and asecond color filter 174 c, andmicrolens layer 170 c includes afirst microlens 176 c and asecond microlens 178 c. - As shown in
FIG. 5 , firstlight sensing region 118 c includes an extendingportion 218, and extendingportion 218 overlaps with a portion of first source/drain structure 136 c. However, extendingportion 218 of firstlight sensing region 118 c has a thickness smaller than other portions of firstlight sensing region 118 c, so that the extendingportion 218 will not be contact with first source/drain structure 136 c. - Similarly, second
light sensing region 120 c includes an extendingportion 220, and extendingportion 220 overlaps with a portion of second source/drain structure 138 c. However, extendingportion 220 of secondlight sensing region 120 c has a thickness smaller than other portions of secondlight sensing region 120 c, so that the extendingportion 220 will not be contact with secondlight sensing region 120 c. The formation of extendingportions image sensor structure 100 c may be improved. - It should be noted that the numbers of the light sensing regions, color filters, and microlens shown in
FIGS. 1 to 5 are merely examples and the scope of the disclosure is not intended to be limiting. In addition, the relative size of each feature in the figures may not be changed or simplified for better understanding the concept of the disclosure, but the scope of the disclosure is not intended to be limiting. - Generally, isolation structures are used to separate neighboring light sensing regions in image sensor structures. However, as the size of the image sensor structure shrink, isolation formed by implantation may not be able to prevent cross-talk and/or blooming. Therefore, isolation structure 112 (or
isolation structures isolation trench 108 and depositing isolating material, such as oxide, inisolation trench 108 is formed in accordance with some embodiments.Isolation structure 112 can be seen as a deep trench isolation structure, and the risk of cross-talk and/or blooming can be reduced. - However, when
isolation structure 112, which is formed by isolation material, is formed to separate firstlight sensing region 118 and secondlight sensing region 120, sharing the pixels (e.g. source/drain structures) also become difficult. For example, complicated and additional conductive features may be required. However, the space for forming these conductive features may result in smaller sensing area and higher capacitance. Therefore, in some embodiments, wide contact 152 (orwide contacts drain structure 136 and second source/drain structure 138 formed at the opposite sides ofisolation structure 112. That is, additional and complicated conductive features are not required, and the size of first source/drain structure 136 and second source/drain structure 138 can be reduced. Accordingly, the capacitance of the floating diffusion node may be reduced. - Furthermore, since the size of first source/
drain structure 136 and second source/drain structure 138 may be reduced, the size of firstlight sensing region 118 and secondlight sensing region 120 may be enlarged. Therefore, the quantum efficiency may be increased, and the performance ofimage sensor structure 100 a (orimage sensor structures - In addition, as shown in
FIG. 4B , firsthard mask layer 222 is formed overfirst gate structure 122 b in accordance with some embodiments. Therefore,wide contact 152 b may be self-aligned to firstlight sensing region 136 b and secondlight sensing region 138 b. Accordingly, the size of firstlight sensing region 136 b and secondlight sensing region 138 b may be further reduced and the size of firstlight sensing region 118 b and secondlight sensing region 120 b may be further enlarged. - Embodiments of image sensor structures and methods for manufacturing the same are provided. The image sensor structure includes an isolation structure formed in a substrate. A first light sensing region is formed in a first region of the substrate, and a second light sensing region is formed in a second region of the substrate. A first source/drain structure is formed in the first region adjacent to one side of the isolation structure, and a second source/drain structure is formed in the second region adjacent to the other side of the isolation structure. A contact is formed over a portion of the first source/drain structure, the isolation structure, and a portion of the second source/drain structure, so that the first source/drain structure and the second source/drain structure can be electrically connected by the contact.
- In some embodiments, a method for manufacturing an image sensor structure is provided. The method for manufacturing the image sensor structure includes forming an isolation structure in a substrate to divide the substrate into a first region and a second region and forming a first light sensing region in the first region and a second light sensing region in the second region. The method for manufacturing the image sensor structure further includes forming a first gate structure over the first region and a second gate structure over the second region. In addition, the first gate structure and the second gate structure are positioned at a front side of the substrate. The method for manufacturing the image sensor structure further includes forming a first source/drain structure adjacent to the first gate structure and a second source/drain structure adjacent to the second gate structure and forming an interlayer dielectric layer over the front side of the substrate to cover the first gate structure and the second gate structure. The method for manufacturing the image sensor structure further includes forming a contact trench through the interlayer dielectric layer, such that a portion of the first source/drain structure, a portion of the second source/drain structure, and the isolation structure are exposed by the contact trench. The method for manufacturing the image sensor structure further includes forming a contact in the contact trench.
- In some embodiments, a method for manufacturing an image sensor structure is provided. The method for manufacturing the image sensor structure includes forming an isolation structure in a substrate and forming a first source/drain structure and a second source/drain structure at opposite sides of the isolation structure. The method for manufacturing the image sensor structure further includes forming an interlayer dielectric layer over the substrate to cover the first source/drain structure and the second source/drain structure and forming a contact trench through the interlayer dielectric layer, such that a portion of the first source/drain structure, a portion of the second source/drain structure, and the isolation structure are exposed by the contact trench. The method for manufacturing the image sensor structure further includes forming a contact in the contact trench.
- In some embodiments, a method for manufacturing an image sensor structure is provided. The method for manufacturing the image sensor structure includes forming an isolation trench in a substrate and forming an isolation structure in the isolation trench. The method for manufacturing the image sensor structure further includes forming a first source/drain structure and a second source/drain structure at opposite sides of the isolation structure and . . . . The method for manufacturing the image sensor structure further includes forming a contact over a portion of the first source/drain structure, a portion of the second source/drain structure, and the isolation structure.
- The foregoing outlines features of several embodiments so that those skilled in the art may better understand the aspects of the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.
Claims (20)
1. A method for manufacturing an image sensor structure, comprising:
forming an isolation structure in a substrate to divide the substrate into a first region and a second region;
forming a first light sensing region in the first region and a second light sensing region in the second region;
forming a first gate structure over the first region and a second gate structure over the second region, wherein the first gate structure and the second gate structure are positioned at a front side of the substrate;
forming a first source/drain structure adjacent to the first gate structure and a second source/drain structure adjacent to the second gate structure;
forming an interlayer dielectric layer over the front side of the substrate to cover the first gate structure and the second gate structure;
forming a contact trench through the interlayer dielectric layer, such that a portion of the first source/drain structure, a portion of the second source/drain structure, and the isolation structure are exposed by the contact trench; and
forming a contact in the contact trench.
2. The method for manufacturing an image sensor structure as claimed in claim 1 , wherein forming the isolation structure comprises:
forming an isolation trench in the substrate; and
depositing an isolation material in the isolation trench.
3. The method for manufacturing an image sensor structure as claimed in claim 2 , wherein the isolation material comprises silicon nitride, silicon oxide, or polysilicon.
4. The method for manufacturing an image sensor structure as claimed in claim 1 , further comprising:
forming a first hard mask structure over the first gate structure,
wherein a portion of the first hard mask structure is exposed by the contact trench.
5. The method for manufacturing an image sensor structure as claimed in claim 4 , wherein a portion of the contact is overlapped with a portion of the first gate structure and is separated from the first gate structure by the first hard mask structure.
6. The method for manufacturing an image sensor structure as claimed in claim 1 , further comprising:
forming an interconnect structure over the interlayer dielectric layer; and
forming a color filter layer over a back side of the substrate.
7. The method for manufacturing an image sensor structure as claimed in claim 1 , further comprising:
polishing the substrate from its back side until the first light sensing region and the second light sensing region are exposed.
8. A method for manufacturing an image sensor structure, comprising:
forming an isolation structure in a substrate;
forming a first source/drain structure and a second source/drain structure at opposite sides of the isolation structure;
forming an interlayer dielectric layer over the substrate to cover the first source/drain structure and the second source/drain structure;
forming a contact trench through the interlayer dielectric layer, such that a portion of the first source/drain structure, a portion of the second source/drain structure, and the isolation structure are exposed by the contact trench; and
forming a contact in the contact trench.
9. The method for manufacturing an image sensor structure as claimed in claim 8 , wherein the isolation structure comprises silicon nitride, silicon oxide, or polysilicon.
10. The method for manufacturing an image sensor structure as claimed in claim 8 , further comprising:
forming a first light sensing region adjacent to the first source/drain structure and a second light sensing region adjacent to the second source/drain structure.
11. The method for manufacturing an image sensor structure as claimed in claim 8 , further comprising:
forming a first gate structure adjacent to the first source/drain structure and a second gate structure adjacent to the second source/drain structure.
12. The method for manufacturing an image sensor structure as claimed in claim 11 , wherein a portion of the contact overlaps with a portion of the first gate structure.
13. The method for manufacturing an image sensor structure as claimed in claim 12 , wherein the contact and the first gate structure are separated by a hard mask structure.
14. The method for manufacturing an image sensor structure as claimed in claim 8 , further comprising:
forming an interconnect structure over the interlayer dielectric layer; and
forming a color filter layer over a back side of the substrate.
15. A method for manufacturing an image sensor structure, comprising:
forming an isolation trench in a substrate;
forming an isolation structure in the isolation trench;
forming a first source/drain structure and a second source/drain structure at opposite sides of the isolation structure; and
forming a contact over a portion of the first source/drain structure, a portion of the second source/drain structure, and the isolation structure.
16. The method for manufacturing an image sensor structure as claimed in claim 15 , further comprising:
forming a first light sensing region adjacent to the first source/drain structure and a second light sensing region adjacent to the second source/drain structure.
17. The method for manufacturing an image sensor structure as claimed in claim 16 , further comprising:
forming a first gate structure adjacent to the first source/drain structure and a second gate structure adjacent to the second source/drain structure.
18. The method for manufacturing an image sensor structure as claimed in claim 15 , further comprising:
forming an interlayer dielectric layer over a front side of the substrate, wherein the contact passes through the interlayer dielectric layer;
forming an interconnect structure over the interlayer dielectric layer; and
forming a color filter layer over a back side of the substrate.
19. The method for manufacturing an image sensor structure as claimed in claim 16 , further comprising:
polishing the substrate from its back side until the first light sensing region and the second light sensing region are exposed.
20. The method for manufacturing an image sensor structure as claimed in claim 15 , further comprising:
forming a color filter layer over a back side of the substrate,
wherein the contact is formed over a front side of the substrate.
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Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2019220945A1 (en) | 2018-05-18 | 2019-11-21 | ソニーセミコンダクタソリューションズ株式会社 | Imaging element and electronic device |
WO2023203811A1 (en) * | 2022-04-18 | 2023-10-26 | ソニーセミコンダクタソリューションズ株式会社 | Optical detection device |
DE102018121990B4 (en) | 2018-02-27 | 2024-02-08 | Samsung Electronics Co., Ltd. | IMAGE SENSORS |
Families Citing this family (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2017204510A (en) * | 2016-05-09 | 2017-11-16 | キヤノン株式会社 | Method of manufacturing photoelectric conversion device |
CN108321116A (en) | 2017-01-17 | 2018-07-24 | 联华电子股份有限公司 | Integrated circuit structure with semiconductor element and its manufacturing method |
US10043841B1 (en) * | 2017-07-31 | 2018-08-07 | Taiwan Semiconductor Manufacturing Co., Ltd. | Image sensor device and method for forming the same |
US10373999B2 (en) | 2017-09-29 | 2019-08-06 | Taiwan Semiconductor Manufacturing Company Ltd. | Image sensor and associated fabricating method |
KR102427639B1 (en) | 2017-11-13 | 2022-08-01 | 삼성전자주식회사 | Image sensing device |
CN107948495B (en) * | 2018-01-12 | 2020-11-20 | 信利光电股份有限公司 | Subregion formation of image sensitization chip and module, camera device of making a video recording |
CN111656511A (en) * | 2018-04-04 | 2020-09-11 | 松下知识产权经营株式会社 | Electronic device |
TWI685958B (en) * | 2018-12-13 | 2020-02-21 | 力晶積成電子製造股份有限公司 | Image sensor and manufacturing method thereof |
TW202118029A (en) * | 2019-06-26 | 2021-05-01 | 日商索尼半導體解決方案公司 | Semiconductor device and manufacturing method for same |
JPWO2020262131A1 (en) * | 2019-06-26 | 2020-12-30 | ||
US11309348B2 (en) * | 2019-09-11 | 2022-04-19 | Taiwan Semiconductor Manufacturing Company, Ltd. | High density image sensor |
JP2022055214A (en) * | 2020-09-28 | 2022-04-07 | ソニーセミコンダクタソリューションズ株式会社 | Solid-state imaging device, electronic apparatus, and manufacturing method of solid-state imaging device |
Citations (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7315014B2 (en) * | 2005-08-30 | 2008-01-01 | Micron Technology, Inc. | Image sensors with optical trench |
US20100155868A1 (en) * | 2008-12-24 | 2010-06-24 | Hoon Jang | Image sensor and manufacturing method thereof |
US20110108939A1 (en) * | 2009-11-10 | 2011-05-12 | Stmicroelectronics (Crolles 2) Sas | Method for forming a back-side illuminated image sensor |
US20110156186A1 (en) * | 2009-12-28 | 2011-06-30 | Kabushiki Kaisha Toshiba | Solid-state imaging device |
US20130130456A1 (en) * | 2010-05-26 | 2013-05-23 | Taiwan Semiconductor Manufacturing Company, Ltd. | Integrated circuits and manufacturing methods thereof |
US20140054662A1 (en) * | 2011-03-02 | 2014-02-27 | Sony Corporation | Solid-state imaging device, manufacturing method of solid-state imaging device, and electronic device |
US20140077323A1 (en) * | 2012-09-19 | 2014-03-20 | Aptina Imaging Corporation | Imaging systems with backside illuminated near infrared imaging pixels |
US20140110809A1 (en) * | 2012-10-23 | 2014-04-24 | Kabushiki Kaisha Toshiba | Method of manufacturing solid-state imaging device and solid-state imaging device |
US20140353468A1 (en) * | 2013-05-31 | 2014-12-04 | SK Hynix Inc. | Isolation structure and method for forming the same, and image sensor including the isolation structure and method for fabricating the image sensor |
US20150243697A1 (en) * | 2014-02-27 | 2015-08-27 | Taiwan Semiconductor Manufacturing Co., Ltd. | Image sensor device and method for forming the same |
Family Cites Families (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8120079B2 (en) * | 2002-09-19 | 2012-02-21 | Quantum Semiconductor Llc | Light-sensing device for multi-spectral imaging |
JP5354765B2 (en) * | 2004-08-20 | 2013-11-27 | カミヤチョウ アイピー ホールディングス | Manufacturing method of semiconductor device having three-dimensional laminated structure |
JP4525671B2 (en) * | 2006-12-08 | 2010-08-18 | ソニー株式会社 | Solid-state imaging device |
US7893468B2 (en) * | 2008-05-30 | 2011-02-22 | International Business Machines Corporation | Optical sensor including stacked photodiodes |
FR2950504B1 (en) * | 2009-09-24 | 2012-06-22 | St Microelectronics Sa | PICTURE SENSOR PIXEL CIRCUIT |
US8390089B2 (en) | 2010-07-27 | 2013-03-05 | Taiwan Semiconductor Manufacturing Company, Ltd. | Image sensor with deep trench isolation structure |
US8273610B2 (en) * | 2010-11-18 | 2012-09-25 | Monolithic 3D Inc. | Method of constructing a semiconductor device and structure |
JP5606961B2 (en) * | 2011-02-25 | 2014-10-15 | ルネサスエレクトロニクス株式会社 | Semiconductor device |
JP2012204403A (en) * | 2011-03-23 | 2012-10-22 | Toshiba Corp | Solid-state imaging device and method of manufacturing the same |
JP2013143532A (en) * | 2012-01-12 | 2013-07-22 | Toshiba Corp | Semiconductor device |
JP5696081B2 (en) * | 2012-03-23 | 2015-04-08 | 株式会社東芝 | Solid-state imaging device |
KR101968197B1 (en) * | 2012-05-18 | 2019-04-12 | 삼성전자주식회사 | Image sensor and method of forming the same |
US8796748B2 (en) | 2012-08-08 | 2014-08-05 | Taiwan Semiconductor Manufacturing Company, Ltd. | Transistors, methods of manufacture thereof, and image sensor circuits |
JP2014060199A (en) * | 2012-09-14 | 2014-04-03 | Toshiba Corp | Method of manufacturing solid-state imaging device and solid-state imaging device |
KR101959715B1 (en) * | 2012-11-06 | 2019-03-20 | 삼성전자 주식회사 | Semiconductor device |
US9048126B2 (en) | 2013-03-12 | 2015-06-02 | Taiwan Semiconductor Manufacturing Company, Ltd. | Methods for measuring the full well capacity of CMOS image sensors |
US9054007B2 (en) * | 2013-08-15 | 2015-06-09 | Omnivision Technologies, Inc. | Image sensor pixel cell with switched deep trench isolation structure |
JP6292049B2 (en) * | 2013-09-02 | 2018-03-14 | ソニー株式会社 | Semiconductor device and manufacturing method thereof |
US9887234B2 (en) | 2014-01-24 | 2018-02-06 | Taiwan Semiconductor Manufacturing Company Limited | CMOS image sensor and method for forming the same |
JP6200835B2 (en) * | 2014-02-28 | 2017-09-20 | ルネサスエレクトロニクス株式会社 | Semiconductor device and manufacturing method thereof |
US9293490B2 (en) * | 2014-03-14 | 2016-03-22 | Taiwan Semiconductor Manufacturing Company, Ltd. | Deep trench isolation with air-gap in backside illumination image sensor chips |
US9344200B2 (en) * | 2014-10-08 | 2016-05-17 | International Business Machines Corporation | Complementary metal oxide semiconductor device with III-V optical interconnect having III-V epitaxial semiconductor material formed using lateral overgrowth |
US20160204158A1 (en) * | 2015-01-12 | 2016-07-14 | United Microelectronics Corp. | Complementary metal oxide semiconductor image sensor device and method of forming the same |
-
2015
- 2015-10-30 US US14/928,604 patent/US9620548B1/en active Active
-
2016
- 2016-08-25 CN CN201610717079.9A patent/CN106653780A/en active Pending
- 2016-10-25 TW TW105134398A patent/TW201727883A/en unknown
-
2017
- 2017-03-29 US US15/472,814 patent/US9978805B2/en active Active
Patent Citations (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7315014B2 (en) * | 2005-08-30 | 2008-01-01 | Micron Technology, Inc. | Image sensors with optical trench |
US20100155868A1 (en) * | 2008-12-24 | 2010-06-24 | Hoon Jang | Image sensor and manufacturing method thereof |
US20110108939A1 (en) * | 2009-11-10 | 2011-05-12 | Stmicroelectronics (Crolles 2) Sas | Method for forming a back-side illuminated image sensor |
US20110156186A1 (en) * | 2009-12-28 | 2011-06-30 | Kabushiki Kaisha Toshiba | Solid-state imaging device |
US20130130456A1 (en) * | 2010-05-26 | 2013-05-23 | Taiwan Semiconductor Manufacturing Company, Ltd. | Integrated circuits and manufacturing methods thereof |
US20140054662A1 (en) * | 2011-03-02 | 2014-02-27 | Sony Corporation | Solid-state imaging device, manufacturing method of solid-state imaging device, and electronic device |
US9502450B2 (en) * | 2011-03-02 | 2016-11-22 | Sony Corporation | Solid-state imaging device, manufacturing method of solid-state imaging device, and electronic device |
US20140077323A1 (en) * | 2012-09-19 | 2014-03-20 | Aptina Imaging Corporation | Imaging systems with backside illuminated near infrared imaging pixels |
US20140110809A1 (en) * | 2012-10-23 | 2014-04-24 | Kabushiki Kaisha Toshiba | Method of manufacturing solid-state imaging device and solid-state imaging device |
US20140353468A1 (en) * | 2013-05-31 | 2014-12-04 | SK Hynix Inc. | Isolation structure and method for forming the same, and image sensor including the isolation structure and method for fabricating the image sensor |
US20150243697A1 (en) * | 2014-02-27 | 2015-08-27 | Taiwan Semiconductor Manufacturing Co., Ltd. | Image sensor device and method for forming the same |
US9627426B2 (en) * | 2014-02-27 | 2017-04-18 | Taiwan Semiconductor Manufacturing Co., Ltd. | Image sensor device and method for forming the same |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102018121990B4 (en) | 2018-02-27 | 2024-02-08 | Samsung Electronics Co., Ltd. | IMAGE SENSORS |
WO2019220945A1 (en) | 2018-05-18 | 2019-11-21 | ソニーセミコンダクタソリューションズ株式会社 | Imaging element and electronic device |
EP4138137A1 (en) | 2018-05-18 | 2023-02-22 | Sony Semiconductor Solutions Corporation | Image sensor and electronic device |
WO2023203811A1 (en) * | 2022-04-18 | 2023-10-26 | ソニーセミコンダクタソリューションズ株式会社 | Optical detection device |
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